In MediaWiki, revisions compared in a diff do not need to
belong to the same article.  So for example, to compare the
current revision of...(488139) to the current revision of
...(505754), you can use the URL
https://fedoraproject.org/w/index.php?diff=505754&oldid=488139
This is not as convenient (or obvious :-)) as your approach,

Is there a way to click into that, or do you just know the URL and substituted the IDs by hand? How did you get the IDs of the two pages in the first place?